WRX RA powered VW 1303 beetle cabrio with a bit of Porsche
Discussion
Update from the mapping session..
The engine runs really well, nice and smooth with very good early turbo spool. By the end of the run the new chargecooler was still stone cold so all in fairly happy! The downside is that the clutch can't take the torque, we were limited to just under 1 bar boost pressure which is fine for running in but I'll have to sort out an uprated one before getting the final map up to full boost done.
The engine runs really well, nice and smooth with very good early turbo spool. By the end of the run the new chargecooler was still stone cold so all in fairly happy! The downside is that the clutch can't take the torque, we were limited to just under 1 bar boost pressure which is fine for running in but I'll have to sort out an uprated one before getting the final map up to full boost done.
Bit of an update:
I made up a new bulkhead panel to properly clear the new chargecooler
New stage 1 KEP clutch, this is rated to 550ft lbs torque so fine for my target level of about 450..
The release bearings changed to include a plastic liner, this meant that I needed to buy a new bearing guide tube from Porsche..
While the chargecooler was off again I thought I would take the opportunity to improve the mounting and filling system. Here is a new support bracket using a locost type suspension rubber bushing I had lying around
New filler neck welded to the chargecooler makes the pipework much neater and is obviously much easier to bleed and keep full. The filler neck was decent and came from Mishimoto, most others were pretty flimsy pressed items.
All fitted again, the chargecooler is much better mounted and easier to fill now.
I made up a new bulkhead panel to properly clear the new chargecooler
New stage 1 KEP clutch, this is rated to 550ft lbs torque so fine for my target level of about 450..
The release bearings changed to include a plastic liner, this meant that I needed to buy a new bearing guide tube from Porsche..
While the chargecooler was off again I thought I would take the opportunity to improve the mounting and filling system. Here is a new support bracket using a locost type suspension rubber bushing I had lying around
New filler neck welded to the chargecooler makes the pipework much neater and is obviously much easier to bleed and keep full. The filler neck was decent and came from Mishimoto, most others were pretty flimsy pressed items.
All fitted again, the chargecooler is much better mounted and easier to fill now.
A chargecooler is an intercooler which is cooled by a jacket of water/coolant rather than air like most turbo systems. The water has a far higher heat capacity so is better at cooling the intake charge, particularly when in my case I don't really have space for an air/air as they are bigger and need a lot of direct air flow.
As the car is more or less done now I thought I'd post a bit of a summary of the final spec and some finished pictures (still waiting to get a proper photoshoot sorted!). In the mean time I've had it on the test track at work and got it up to an easy 150mph (GPS not speedo) and there was plenty more in it. Just need to give it a clean ready for a trip over to Spa next weekend..
Body
oMain body restored with new heater channels, strengtheners, bulkhead, etc etc
oSpare wheel well modified to take main radiator and charge-cooler radiator
oFuel tank extended, baffled and fitted with internal up-rated fuel pump (HRC 310lpm)
oRear end removable on frame, VW bus inspection hatch above engine
oFront wings: 2” wider in fibreglass
oRear wings: 40mm wider in steel with forced cold air intake incorporated into left hand wing
oK&N panel air filter built in to inner wing, with water drain
oLengthened bumper irons with stock bumpers
oRepaint in original colour (Schwartz Metallic)
oGerman Sonnenland roof
•Chassis
oCustom framehorns, torsion housing central section removed
oCustom perimeter frame rails with one-off bead-rolled floors, finished in epoxy mastic 121.
oOBP reverse mounted pedal box with twin brake master cylinders for adjustable bias and hydraulic clutch under false floor
oFront: Kerscher coil-over struts, heavy duty anti-roll bar
oRear: IRS with Protech coil-over dampers and swing axle length torsion bars, 944 anti-roll bar
o19” Porsche Carrera Sport wheels, 10j rear, 8,5j front
oVredestein Ultrac Sessenta tyres, 265/30R19 & 235/35R19
oPorsche 911 (996) brembo brakes front & rear
oBraided hoses, 911 fluid reservoir.
oSpacesaver 996 spare wheel
•Powertrain
oRebuilt subaru EJ257 shortblock (2.5l STI), forged supertech pistons, rebuilt V4 sti heads, ARP 11mm head studs, external oil breather catch tank, shortened/extended sump with RCM baffle plate, Garrett SC46 turbo, ported headers with custom 2” crosspipe, 3” bellmouth from turbo back, magnaflow 3" muffler, Nismo 740cc injectors, ESL daughterboard mapped by Bob Rawle, Aeromotive FPR on reversed parallel fuel rails, new-age subaru coilpack conversion. Estimated 400-450bhp, 450ftlbs.
oCustom charge-cooler system with bosch water pump and Pace pre-rad, inlet manifold spacers/insulaters
oCooling system modified to external thermostat with Pace sierra cosworth radiator, fans controlled by ECU
o1989 Porsche 911 ‘G50 shortnose’ transaxle fitted with rebuilt 964 RS LSD (80/20). 930 CVs, aftermarket axles and drive flanges, KEP uprated Porsche stage 1 clutch (550ftlbs)
•Interior
•Square weave carpets
•Heated Porsche 996 sports seats and seatbelts
•Rear seat modified to clear transmission tunnel
•Dashboard widened to fit early Porsche 924 gauges with additional Stack Oil pressure and turbo pressure gauges. Mini switches.
•Seats and dash re-trimmed in saddle tan leather by Auto-trim, Leicester
•Alpine CDA-X001 head unit, Rainbow component speakers up front in one-off fibreglass foot well enclosures, pioneer rear speakers in kick panels
•One-off heater system built into stock duct system, stock dash controls with t25 fan switch & electronic Ford heater valve
Body
oMain body restored with new heater channels, strengtheners, bulkhead, etc etc
oSpare wheel well modified to take main radiator and charge-cooler radiator
oFuel tank extended, baffled and fitted with internal up-rated fuel pump (HRC 310lpm)
oRear end removable on frame, VW bus inspection hatch above engine
oFront wings: 2” wider in fibreglass
oRear wings: 40mm wider in steel with forced cold air intake incorporated into left hand wing
oK&N panel air filter built in to inner wing, with water drain
oLengthened bumper irons with stock bumpers
oRepaint in original colour (Schwartz Metallic)
oGerman Sonnenland roof
•Chassis
oCustom framehorns, torsion housing central section removed
oCustom perimeter frame rails with one-off bead-rolled floors, finished in epoxy mastic 121.
oOBP reverse mounted pedal box with twin brake master cylinders for adjustable bias and hydraulic clutch under false floor
oFront: Kerscher coil-over struts, heavy duty anti-roll bar
oRear: IRS with Protech coil-over dampers and swing axle length torsion bars, 944 anti-roll bar
o19” Porsche Carrera Sport wheels, 10j rear, 8,5j front
oVredestein Ultrac Sessenta tyres, 265/30R19 & 235/35R19
oPorsche 911 (996) brembo brakes front & rear
oBraided hoses, 911 fluid reservoir.
oSpacesaver 996 spare wheel
•Powertrain
oRebuilt subaru EJ257 shortblock (2.5l STI), forged supertech pistons, rebuilt V4 sti heads, ARP 11mm head studs, external oil breather catch tank, shortened/extended sump with RCM baffle plate, Garrett SC46 turbo, ported headers with custom 2” crosspipe, 3” bellmouth from turbo back, magnaflow 3" muffler, Nismo 740cc injectors, ESL daughterboard mapped by Bob Rawle, Aeromotive FPR on reversed parallel fuel rails, new-age subaru coilpack conversion. Estimated 400-450bhp, 450ftlbs.
oCustom charge-cooler system with bosch water pump and Pace pre-rad, inlet manifold spacers/insulaters
oCooling system modified to external thermostat with Pace sierra cosworth radiator, fans controlled by ECU
o1989 Porsche 911 ‘G50 shortnose’ transaxle fitted with rebuilt 964 RS LSD (80/20). 930 CVs, aftermarket axles and drive flanges, KEP uprated Porsche stage 1 clutch (550ftlbs)
•Interior
•Square weave carpets
•Heated Porsche 996 sports seats and seatbelts
•Rear seat modified to clear transmission tunnel
•Dashboard widened to fit early Porsche 924 gauges with additional Stack Oil pressure and turbo pressure gauges. Mini switches.
•Seats and dash re-trimmed in saddle tan leather by Auto-trim, Leicester
•Alpine CDA-X001 head unit, Rainbow component speakers up front in one-off fibreglass foot well enclosures, pioneer rear speakers in kick panels
•One-off heater system built into stock duct system, stock dash controls with t25 fan switch & electronic Ford heater valve
dm46 said:
Wow! What does it drive like?
Very quick kinda goes without saying! The relatively short wheel base and wide track definitely keeps you on your toes but when it does break traction it does so nice and progressively. The ride is really good due to relatively soft springs which helps with the weight of the big wheels. I did try driving it on my original 17" cup 2 alloys with taller tyres but it actually felt really soft and nowhere near as sharp so I'll be sticking with the 19s, maybe some 18s with semi-slick tyres for serious use but where do I stop? Controls are fairly heavy but my wife can drive it round the block so can't be too bad, I may yet fit a slightly smaller clutch master cylinder as is common with the Ultima guys (same clutch) and I'm quite tempted to fit a dual circuit brake servo but that would mean losing some luggage space somewhere unless I can think of somewhere creative to put it. I'm sure I'll keep tinkering but this is as close to finished as these cars ever get!Rich
Dr G said:
Did you take a picture on the 17s?
I understand your reasoning for staying with the bigguns but the only thing I don't absolutely love about your car is that to my eye it looks a little over wheeled.
This is from before the full-on build with stock width wingsI understand your reasoning for staying with the bigguns but the only thing I don't absolutely love about your car is that to my eye it looks a little over wheeled.
The wings are also way too wide for the old wheels now too. I like to have them filling the arch rather than being lost..
5potTurbo said:
Always loved this build thread.... should the car ever come up for sale.... 
lol, I'm not planning on selling any time soon, what's this kind of thing worth? My projects seem to be quite specialist markets when I come to sell with a fairly small number of people as they tend to grate with the 'purists'! I must have at least £25k in parts in it. Sadly it may be worth more as parts..Road trip to Spa for ‘Le Bug Show’ was awesome, loads of cars I've never seen before and after seeing other pictures plenty I missed so I'll definitely be back! Was great to get a chance to drive around the track and got a top 20 award which finished off a top weekend 
I also finally got the photoshoot for Volksworld done with some strange attachments, should be some good action shots and I can't wait to see them ( http://www.stevehallphotography.net).
After the trip to Spa, the race style compact boots finally gave up with dealing with the CV angle. They are mainly designed for race cars and are basically an inverted cone with little give so not surprising really. They were necessary to clear the coil-over springs. This picture is from underneath with the car on a 2 post lift and the suspension at full rebound so definitely not the worst position, the damper swings closer to the axle at ride height.
The long term fix was always to relocate the coil-over. I had a spare pair of trailing arms from a 944, these are identical to the beetle ones with the exception of some internal strengthening.
I made up new curved section to take a scallop out of the arm and also reweld the lower damper mount about 15mm further forwards.
All back together ready for clean up and paint.
Better view showing the additional clearance made.
As before this is with the suspension in full droop but now with a nice big silicone off road style CV boot that is designed for much more angularity than I will subject it to. At ride height I can get a finger between the spring and boot so clearance is no longer an issue. While I was at it I also fitted the 944 spring plates with the built in capability of a camber bolt anti-roll bar fitting to set the camber, it is also designed to take a toe adjustment tool. I had to lose the ride height adjustment due to clearance problems with the wheel but with the adjustable coil-overs this really isn't an issue for me...
I also finally got the photoshoot for Volksworld done with some strange attachments, should be some good action shots and I can't wait to see them ( http://www.stevehallphotography.net).
After the trip to Spa, the race style compact boots finally gave up with dealing with the CV angle. They are mainly designed for race cars and are basically an inverted cone with little give so not surprising really. They were necessary to clear the coil-over springs. This picture is from underneath with the car on a 2 post lift and the suspension at full rebound so definitely not the worst position, the damper swings closer to the axle at ride height.
The long term fix was always to relocate the coil-over. I had a spare pair of trailing arms from a 944, these are identical to the beetle ones with the exception of some internal strengthening.
I made up new curved section to take a scallop out of the arm and also reweld the lower damper mount about 15mm further forwards.
All back together ready for clean up and paint.
Better view showing the additional clearance made.
As before this is with the suspension in full droop but now with a nice big silicone off road style CV boot that is designed for much more angularity than I will subject it to. At ride height I can get a finger between the spring and boot so clearance is no longer an issue. While I was at it I also fitted the 944 spring plates with the built in capability of a camber bolt anti-roll bar fitting to set the camber, it is also designed to take a toe adjustment tool. I had to lose the ride height adjustment due to clearance problems with the wheel but with the adjustable coil-overs this really isn't an issue for me...
Time for a mini project! A while back during the MOT test I was slightly concerned with how much the wheels moved about when the tester spread the front axle on the pads. Having seen a few designs of A arms at Spa and online on the boxergasse forum I've decided to give it a go myself! I wanted to do it as a completely bolt on swap. Part of this change is to de-couple the stock anti-roll bar from the geometry so this will be spaced down underneath the A arm. I've seen people put it above but my radiator is in the way and I have plenty of ground clearance.
The inner spherical joint will be M10 and the forward tension link section will be M14, I will also be using sealed boots to keep them weather tight. At the spindle I'm using the original design ball joint. Some people re-position the lower axis as they run very low.
Before I took the stock suspension off, I put the car on stands and with the steering dead ahead and a vertical level marked up the position to the floor. This is obviously just to get the geometry about right, I can fine tune it afterwards.
The key part to the swap is creating a forward bracket, this aluminium block spaces the anti-roll bar downwards with the stock saddle clamp and gives plenty of meat to mount the forward joint.
The block fitted, not how it is fitted to the chassis form. My mate, Seb, machined up some tube end fittings for it.
The first lateral link tacked together
and fitted to the car, now to align the hub and measure up for the tension link. The last bit will be to work out how to connect the anti-roll bar.
Tension link tacked in at nominal geometry position. Some people will fit a clevis type joint to the lateral part but I only wanted minimal adjustment. Welded will give better stiffness.
I trawled ebay for a nice short anti-roll bar that I thought I could adapt and ended up with this from a Mk2 Ford Mondeo, less than £5 delivered for the pair! It was a case of making up some fairly simple adapters to bolt on to the standard 1303 anti-roll bar ends.
Brackets to weld on to the new A arms
Finished A arm ready for paint
Finished 'kit' ready to be fitted! Note I did machine down the blocks some more compared to earlier pictures to maintain the stock pick up position heights and maximise ground clearance.
Ball joint pressed in and rod ends adjusted with their rubber boots to give them a bit more life
All done!
Closer view of one side..
So, the verdict: in summary well worth it! The front end feels so much more alive and communicative but NVH is hardly affected at all. The tyres seem to work a lot better as they are not moving around so much and the steering is even a bit lighter too. Even on motorways you can feel what's going on with the most subtle of movements. Overall it just gives so much more confidence in what the car i doing and that means a lot!
For anybody else that wants to try something similar this is what I used:
Inner joints: M10 male rod ends with high misalignment spacers
Forward joints: M14 rod ends with standard misalignment spacer, additional 18mm spacer inboard
Stock lower strut ball joints
1 1/2" diameter 0.1" wall thickness CDS tubing
Mk 2 Ford Mondeo/Cougar rear anti-roll bar links
If you can't work out the rest then frankly you probably shouldn't be trying to copy it!!
Oh, I know it's short notice but I'll be in it tomorrow for the Jaguar sunday service if anybody wants a nose..
The inner spherical joint will be M10 and the forward tension link section will be M14, I will also be using sealed boots to keep them weather tight. At the spindle I'm using the original design ball joint. Some people re-position the lower axis as they run very low.
Before I took the stock suspension off, I put the car on stands and with the steering dead ahead and a vertical level marked up the position to the floor. This is obviously just to get the geometry about right, I can fine tune it afterwards.
The key part to the swap is creating a forward bracket, this aluminium block spaces the anti-roll bar downwards with the stock saddle clamp and gives plenty of meat to mount the forward joint.
The block fitted, not how it is fitted to the chassis form. My mate, Seb, machined up some tube end fittings for it.
The first lateral link tacked together
and fitted to the car, now to align the hub and measure up for the tension link. The last bit will be to work out how to connect the anti-roll bar.
Tension link tacked in at nominal geometry position. Some people will fit a clevis type joint to the lateral part but I only wanted minimal adjustment. Welded will give better stiffness.
I trawled ebay for a nice short anti-roll bar that I thought I could adapt and ended up with this from a Mk2 Ford Mondeo, less than £5 delivered for the pair! It was a case of making up some fairly simple adapters to bolt on to the standard 1303 anti-roll bar ends.
Brackets to weld on to the new A arms
Finished A arm ready for paint
Finished 'kit' ready to be fitted! Note I did machine down the blocks some more compared to earlier pictures to maintain the stock pick up position heights and maximise ground clearance.
Ball joint pressed in and rod ends adjusted with their rubber boots to give them a bit more life
All done!
Closer view of one side..
So, the verdict: in summary well worth it! The front end feels so much more alive and communicative but NVH is hardly affected at all. The tyres seem to work a lot better as they are not moving around so much and the steering is even a bit lighter too. Even on motorways you can feel what's going on with the most subtle of movements. Overall it just gives so much more confidence in what the car i doing and that means a lot!
For anybody else that wants to try something similar this is what I used:
Inner joints: M10 male rod ends with high misalignment spacers
Forward joints: M14 rod ends with standard misalignment spacer, additional 18mm spacer inboard
Stock lower strut ball joints
1 1/2" diameter 0.1" wall thickness CDS tubing
Mk 2 Ford Mondeo/Cougar rear anti-roll bar links
If you can't work out the rest then frankly you probably shouldn't be trying to copy it!!
Oh, I know it's short notice but I'll be in it tomorrow for the Jaguar sunday service if anybody wants a nose..
I should have said for those that don't know how the stock suspension is laid out: there is the lateral link and then the anti-roll bar is the only fore-aft location as it goes through a bush in the lateral arm. The extra bushes and the fact a bent spring steel bar is your only link under braking doesn't lead to a particularly well controlled system..
Well I sold my 996 turbo to get the deposit for a Tesla Model S and that is now my daily. Planning a trip down to the south of france in a couple of weeks in that. Just got back from my third trip over to Spa and luckily somebody had a gopro for a 'parade' lap, enjoy!
https://www.youtube.com/watch?v=fpCeQdOplJE
https://www.youtube.com/watch?v=fpCeQdOplJE
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